Rivet analyses referenceBABAR_2007_I756323Measurements of Semi-Leptonic Tau Decays into Three Charged HadronsExperiment: BaBar (PEP-II) Inspire ID: 756323 Status: VALIDATED Authors:
Beam energies: (3.5, 8.0) GeV Run details:
Measurement of tau decays to three charged hadrons using a data sample corresponding to an integrated luminosity of 342 fb$^{-1}$ collected with the BABAR detector at the SLAC PEP-II electron-positron storage ring operating at a center-of-mass energy near 10.58 GeV. Source code: BABAR_2007_I756323.cc 1// -*- C++ -*-
2#include "Rivet/Analysis.hh"
3#include "Rivet/Projections/UnstableParticles.hh"
4
5namespace Rivet {
6
7
8 /// @brief BABAR tau lepton to three charged hadrons
9 ///
10 /// @author Peter Richardson
11 class BABAR_2007_I756323 : public Analysis {
12 public:
13
14 RIVET_DEFAULT_ANALYSIS_CTOR(BABAR_2007_I756323);
15
16
17 void init() {
18 declare(UnstableParticles(), "UFS");
19
20 book(_hist_pipipi_pipipi , 1, 1, 1);
21 book(_hist_pipipi_pipi , 2, 1, 1);
22 book(_hist_Kpipi_Kpipi , 3, 1, 1);
23 book(_hist_Kpipi_Kpi , 4, 1, 1);
24 book(_hist_Kpipi_pipi , 5, 1, 1);
25 book(_hist_KpiK_KpiK , 6, 1, 1);
26 book(_hist_KpiK_KK , 7, 1, 1);
27 book(_hist_KpiK_piK , 8, 1, 1);
28 book(_hist_KKK_KKK , 9, 1, 1);
29 book(_hist_KKK_KK ,10, 1, 1);
30
31 book(_weight_total, "/TMP/weight_total");
32 book(_weight_pipipi, "/TMP/weight_pipipi");
33 book(_weight_Kpipi, "/TMP/weight_Kpipi");
34 book(_weight_KpiK, "/TMP/weight_KpiK");
35 book(_weight_KKK, "/TMP/weight_KKK");
36
37 book(tmp11, 11, 1, 1);
38 book(tmp12, 12, 1, 1);
39 book(tmp13, 13, 1, 1);
40 book(tmp14, 14, 1, 1);
41 }
42
43
44 void analyze(const Event& e) {
45 // Find the taus
46 Particles taus;
47 for(const Particle& p : apply<UnstableParticles>(e, "UFS").particles(Cuts::pid==PID::TAU)) {
48 _weight_total->fill();
49 Particles pip, pim, Kp, Km;
50 unsigned int nstable = 0;
51 // Find the decay products we want
52 findDecayProducts(p, nstable, pip, pim, Kp, Km);
53 if (p.pid() < 0) {
54 swap(pip, pim);
55 swap(Kp, Km );
56 }
57 if (nstable != 4) continue;
58 // pipipi
59 if (pim.size() == 2 && pip.size() == 1) {
60 _weight_pipipi->fill();
61 _hist_pipipi_pipipi->
62 fill((pip[0].momentum()+pim[0].momentum()+pim[1].momentum()).mass());
63 _hist_pipipi_pipi->
64 fill((pip[0].momentum()+pim[0].momentum()).mass());
65 _hist_pipipi_pipi->
66 fill((pip[0].momentum()+pim[1].momentum()).mass());
67 }
68 else if (pim.size() == 1 && pip.size() == 1 && Km.size() == 1) {
69 _weight_Kpipi->fill();
70 _hist_Kpipi_Kpipi->
71 fill((pim[0].momentum()+pip[0].momentum()+Km[0].momentum()).mass());
72 _hist_Kpipi_Kpi->
73 fill((pip[0].momentum()+Km[0].momentum()).mass());
74 _hist_Kpipi_pipi->
75 fill((pim[0].momentum()+pip[0].momentum()).mass());
76 }
77 else if (Kp.size() == 1 && Km.size() == 1 && pim.size() == 1) {
78 _weight_KpiK->fill();
79 _hist_KpiK_KpiK->
80 fill((Kp[0].momentum()+Km[0].momentum()+pim[0].momentum()).mass());
81 _hist_KpiK_KK->
82 fill((Kp[0].momentum()+Km[0].momentum()).mass());
83 _hist_KpiK_piK->
84 fill((Kp[0].momentum()+pim[0].momentum()).mass());
85 }
86 else if (Kp.size() == 1 && Km.size() == 2) {
87 _weight_KKK->fill();
88 _hist_KKK_KKK->
89 fill((Kp[0].momentum()+Km[0].momentum()+Km[1].momentum()).mass());
90 _hist_KKK_KK->
91 fill((Kp[0].momentum()+Km[0].momentum()).mass());
92 _hist_KKK_KK->
93 fill((Kp[0].momentum()+Km[1].momentum()).mass());
94 }
95 }
96 }
97
98
99 void finalize() {
100 if (_weight_pipipi->val() > 0.) {
101 scale(_hist_pipipi_pipipi, 1.0 / *_weight_pipipi);
102 scale(_hist_pipipi_pipi , 0.5 / *_weight_pipipi);
103 }
104 if (_weight_Kpipi->val() > 0.) {
105 scale(_hist_Kpipi_Kpipi , 1.0 / *_weight_Kpipi);
106 scale(_hist_Kpipi_Kpi , 1.0 / *_weight_Kpipi);
107 scale(_hist_Kpipi_pipi , 1.0 / *_weight_Kpipi);
108 }
109 if (_weight_KpiK->val() > 0.) {
110 scale(_hist_KpiK_KpiK , 1.0 / *_weight_KpiK);
111 scale(_hist_KpiK_KK , 1.0 / *_weight_KpiK);
112 scale(_hist_KpiK_piK , 1.0 / *_weight_KpiK);
113 }
114 if (_weight_KKK->val() > 0.) {
115 scale(_hist_KKK_KKK , 1.0 / *_weight_KKK);
116 scale(_hist_KKK_KK , 0.5 / *_weight_KKK);
117 }
118 tmp11->bin(1).set(100*_weight_pipipi->val()/_weight_total->val(),
119 100*sqrt(double(_weight_pipipi->val()))/_weight_total->val());
120 tmp12->bin(1).set(100*_weight_Kpipi->val()/_weight_total->val(),
121 100*sqrt(double(_weight_Kpipi->val()))/_weight_total->val());
122 tmp13->bin(1).set(100*_weight_KpiK->val()/_weight_total->val(),
123 100*sqrt(double(_weight_KpiK->val()))/_weight_total->val());
124 tmp14->bin(1).set(100*_weight_KKK->val()/_weight_total->val(),
125 100*sqrt(double(_weight_KKK->val()))/_weight_total->val());
126 }
127
128
129 private:
130
131 Estimate1DPtr tmp11, tmp12, tmp13, tmp14;
132
133 // Histograms
134 Histo1DPtr _hist_pipipi_pipipi, _hist_pipipi_pipi;
135 Histo1DPtr _hist_Kpipi_Kpipi, _hist_Kpipi_Kpi, _hist_Kpipi_pipi;
136 Histo1DPtr _hist_KpiK_KpiK, _hist_KpiK_KK, _hist_KpiK_piK;
137 Histo1DPtr _hist_KKK_KKK, _hist_KKK_KK;
138
139 // Weights counters
140 CounterPtr _weight_total, _weight_pipipi, _weight_Kpipi, _weight_KpiK, _weight_KKK;
141
142
143 void findDecayProducts(const Particle &mother,
144 unsigned int & nstable,
145 Particles& pip, Particles& pim,
146 Particles& Kp, Particles& Km) {
147 for (const Particle &p : mother.children()) {
148 long id = p.pid();
149 if (id == PID::PI0 )
150 ++nstable;
151 else if (id == PID::K0S)
152 ++nstable;
153 else if (id == PID::PIPLUS) {
154 pip.push_back(p);
155 ++nstable;
156 }
157 else if (id == PID::PIMINUS) {
158 pim.push_back(p);
159 ++nstable;
160 }
161 else if (id == PID::KPLUS) {
162 Kp.push_back(p);
163 ++nstable;
164 }
165 else if (id == PID::KMINUS) {
166 Km.push_back(p);
167 ++nstable;
168 }
169 else if (!p.children().empty()) {
170 findDecayProducts(p, nstable, pip, pim, Kp, Km);
171 }
172 else ++nstable;
173 }
174 }
175
176 };
177
178
179 RIVET_DECLARE_ALIASED_PLUGIN(BABAR_2007_I756323, BABAR_2007_S7266081);
180
181}
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